In MB:
1. I see the seal in the EPC A 003 989 54 85 for about $5, but this may be just sealing tape by meter, I am not sure.
2. Screws N 000000 000453, 6 pcs.
3. Cover - indeed, not available.
If you go for authentic Classic (which is what I would do if I were you in the US), ask them to add sealing tape for this part. I also glued a piece of sound dumpening mat on this cover.